Ok, so I am from Florida and I am very used to be at sea level or even below it. I recently travelled up to upstate New York to aprox. 1,800ft of altitude. In Florida, my easy run are at 7:10-20 pace. Up here, I can't run faster than 7:45. It's about 20 degrees out, but can the 1,800ft of altitude slow me down that much? I tried to do a workout the other day and I couldn't even breath.